Narrative:

After clearing a military MTR X to FL390, I saw an air carrier Y at FL330 as traffic. I believed air carrier Y to be on frequency at the time. I asked MTR X to increase rate of climb to get above the traffic and he acknowledged 'I'll do the best I can.' I then turned MTR X right to establish longitudinal separation and tired to turn air carrier Y. Air carrier Y, however, was not on frequency. I immediately back-coordinated for air carrier Y to turn right and be put on my frequency. There was a slight delay in the delivery of my request which may, or may not have contributed to loss of separation. Supplemental information from acn 216613: action to separate aircraft involved should have been started sooner to provide proper separation. Supplemental information from acn 217016: while in cruise at FL330, flying direct to rosewood VOR, ZID gave us a 20 degree turn to the right, followed almost immediately by instructions to make a steep turn to the right. While in the turn, TCASII 'TA' came on and the screen (30 mi range) showed traffic at 11 O'clock (approximately 4 mi) and 200 ft below. We received a TCASII descent command (1000 FPM), and descended approximately 300-400 ft at which time we were clear of the conflict. ZID changed us to a new frequency while we were in the turn. The new frequency kept us 2-3 mins and changed us again. ATC became rather busy at the time and I didn't discuss with them the particulars of what happened. My speculation is that there was fast climbing aircraft climbing beneath us.

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Original NASA ASRS Text

Title: CTLR CLRED MTR ACFT THROUGH AN OCCUPIED ALT RESULTING IN LTSS.

Narrative: AFTER CLRING A MIL MTR X TO FL390, I SAW AN ACR Y AT FL330 AS TFC. I BELIEVED ACR Y TO BE ON FREQ AT THE TIME. I ASKED MTR X TO INCREASE RATE OF CLB TO GET ABOVE THE TFC AND HE ACKNOWLEDGED 'I'LL DO THE BEST I CAN.' I THEN TURNED MTR X R TO ESTABLISH LONGITUDINAL SEPARATION AND TIRED TO TURN ACR Y. ACR Y, HOWEVER, WAS NOT ON FREQ. I IMMEDIATELY BACK-COORDINATED FOR ACR Y TO TURN R AND BE PUT ON MY FREQ. THERE WAS A SLIGHT DELAY IN THE DELIVERY OF MY REQUEST WHICH MAY, OR MAY NOT HAVE CONTRIBUTED TO LOSS OF SEPARATION. SUPPLEMENTAL INFO FROM ACN 216613: ACTION TO SEPARATE ACFT INVOLVED SHOULD HAVE BEEN STARTED SOONER TO PROVIDE PROPER SEPARATION. SUPPLEMENTAL INFO FROM ACN 217016: WHILE IN CRUISE AT FL330, FLYING DIRECT TO ROSEWOOD VOR, ZID GAVE US A 20 DEG TURN TO THE R, FOLLOWED ALMOST IMMEDIATELY BY INSTRUCTIONS TO MAKE A STEEP TURN TO THE R. WHILE IN THE TURN, TCASII 'TA' CAME ON AND THE SCREEN (30 MI RANGE) SHOWED TFC AT 11 O'CLOCK (APPROX 4 MI) AND 200 FT BELOW. WE RECEIVED A TCASII DSCNT COMMAND (1000 FPM), AND DSNDED APPROX 300-400 FT AT WHICH TIME WE WERE CLR OF THE CONFLICT. ZID CHANGED US TO A NEW FREQ WHILE WE WERE IN THE TURN. THE NEW FREQ KEPT US 2-3 MINS AND CHANGED US AGAIN. ATC BECAME RATHER BUSY AT THE TIME AND I DIDN'T DISCUSS WITH THEM THE PARTICULARS OF WHAT HAPPENED. MY SPECULATION IS THAT THERE WAS FAST CLBING ACFT CLBING BENEATH US.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.